Mechanical drive



Dec. 25, 1956 H. '.J. SMITS 2,775,131

MECHANICAL DRIVE Original Filed NOV. l7 1949 IN VEN TOR.

HUBERTUS JAN SMITS AGENT United States Patent MECHANICAL DRIVE HubertusJan Smits, Eindhoven, Netherlands, assignor to Hartford National Bankand Trust Company, Hartford, Conn., as trustee Original applicationNovember 17, 1949, Serial No. 127,907, now Patent No. 2,664,758, datedJanuary 5, 1954. Divided and this application April 16, 1953, Serial No.356,629 7 Claims priority, application Netherlands November 24, 1948 2Claims. (Cl. 74-221) This invention relates to a driving mechanism andmore particularly to a mechanical drive for operating a turn tableemployed in phonograph apparatus. The present application is adivisional application of my co-pending application Serial No. 127,907,filed November 17, 1949, now Patent No. 2,664,758.

It is an object of the present invention to provide a turntable drivehaving a drive shaft and a driving pulley driven by a motor which drivestwo belts that are disposed on opposite sides of the driving pulley. Thebelts of each of the two guide or driven pulleys are mounted on apivotable plate in such a manner that the plate can be moved laterallyto bring the outer surface of either of said two belts against thecircumference of the driven member. The pulleys on the main drive shaftare of different diameters thus giving different linear speeds to thetwo belts and consequently alternate driving speeds for the drivenmember.

It is a further object of the present invention to provide a phonographturntable drive which permits the alternative playing of records at theusual speeds or the playing of so-called long-playing records at a lowerspeed with the same equipment.

Another object is to provide a vibration-free drive which is especiallyuseful for driving phonographs.

In order that the invention may be carried into effect the same will nowbe described in detail with reference to the accompanying drawings inwhich The single figure is a diagrammatic view of a phonograph turntabledrive embodying the present invention.

Referring more particularly to the drawing in detail, a drive shaft 10has a drive pulley 12 secured thereto. Driven pulleys 13 and 14 arearranged on either side of drive shaft 10 and in the embodiment shownherein a line through the axes of the pulleys 12, 13 and 14 is in asingle plane. It is also within the scope of the present invention toprovide driving and driven pulleys in two planes subtending an angle atthe driving pulley axis. A driving belt 15 passes around the pulley 1.2and the pulley 13 while belt 16 passes around drive shaft 10 and pulley14. Since belts 15 and 16 pass over different circumferences of shaft 10and pulley 12 respectively, ditferent linear speeds are in effect foreach belt. Preferably the shafts of driven pulleys 13 and 14 are mountedon a common mounting plate 17 which pivots at 18 in order to permiteither the belt 15 or belt 16 to be brought alternatively intoengagement with the turntable 4 while the stress of the aforesaid beltsare unvaried substantially 2,775,131 Patented Dec. 25, 1956 for eitherspeed. If desired, the required driving belt pressure against theturntable circumference may be maintained by applying a moment to themounting plate about its pivot and in the direction of the turntable,for example by means of a resilient mounting (not shown). As may be seenfrom the figure, the driving shaft 10 with the pulley 12 is adapted toproject through the aperture 19 of the mounting plate 17.

It is to be understood that the driving shaft 10 to which drive pulley12 is secured is the shaft of a driving motor (not shown), however, itis within the scope of the present invention to couple the drive shaftand drive pulley to a motor shaft by any transmission which issubstantially free from back-lash.

While I have shown and described the preferred embodiment of myinvention, it will be understood that the latter may be embodiedotherwise than as herein specifically illustrated or described and thatin the illustrated embodiment certain changes in the details ofconstruction and in the arrangement of parts may be made withoutdeparting from the underlying idea or principle of the invention withinthe scope of the appended claims.

What I claim is:

l. A phonograph driving mechanism comprising a base, a turntable member,a pivoted mounting plate on said base and provided with an openingtherethrough, a pair of driven pulleys spatially mounted on saidmounting plate, a drive shaft positioned in said opening and locatedbetween said driven pulleys and having two driving pulleys of differentdiameters, two endless belts, one of said belts encircling one of saiddriving pulleys and one of said driven pulleys while the other beltencircles said other driving pulley and other driven pulley, said drivenpulleys being so mounted on said pivoting plate whereby the former canbe moved laterally relative to the axis of said turntable member, andeither of said belts may be thus moved into and out of engagement withthe circumference of said turntable member.

2. A phonograph driving mechanism comprising a base, a turntable member,a pivoting mounting plate on said base and provided with an openingtherethrough, a driven pulley at opposite ends of said mounting plate, adriven shaft positioned in said opening and located between said drivenpulleys and having two driving pulleys of different diameters whereby asingle plane passes through the axes of said drive shaft and drivenpulleys, two endless belts,

one of said belts encircling one of said driving pulleys and one of saiddriven pulleys while the other belt encircles said other driving pulleyand other driven pulley, said driven pulleys being so mounted on saidpivoting plate whereby the former can be moved laterally relative to theaxis of said turntable member and either of said belts may be thus movedinto and out of engagement with the circumference of said turntablemember.

References Cited in the file of this patent UNITED STATES PATENTS365,051 Crowell June 21, 1887 936,948 Russell Oct. 12, 1909 1,152,377Altorfer Aug. 31, 1915 1,169,854 Merritt Feb. 1, 1916 1,350,179 RansomeAug. 17, 1920 2,509,054 Davis May 23, 1950 2,664,758 Smits Jan. 5, 1954

